<template>
  <div id="app">
    <h2>第六题</h2>
    <div class="container">
      <!-- 顶部框模块 -->
      <div class="form-group">
        <div class="input-group">
          <h4>品牌管理</h4>
        </div>
      </div>

      <!-- 数据表格 -->
      <table class="table table-bordered table-hover mt-2">
        <thead>
          <tr>
            <th>编号</th>
            <th>资产名称</th>
            <th>价格</th>
            <th>创建时间</th>
            <th>操作</th>
          </tr>
        </thead>
        <tbody>
          <tr v-for="item in list" :key="item.id">
            <td>{{ item.id }}</td>
            <td>{{ item.name }}</td>

            <!-- 如果价格超过100，就有red这个类 -->
            <td :class="{ red: item.price > 100 }">{{ item.price }}</td>
            <td>{{ item.time | getTime }}</td>
            <td><a href="#" @click.prevent="delBtn(item.id)">删除</a></td>
          </tr>

          <tr style="background-color: #eee" v-show="!list.length <= 0">
            <td>统计:</td>
            <td colspan="2">总价钱为:{{ all }}</td>
            <td colspan="2">平均价:{{ avg }}</td>
          </tr>
        </tbody>

        <tfoot v-show="list.length === 0">
          <tr>
            <td colspan="5" style="text-align: center">暂无数据</td>
          </tr>
        </tfoot>
      </table>

      <!-- 添加资产 -->
      <form class="form-inline">
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="资产名称"
              v-model="name"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <div class="form-group">
          <div class="input-group">
            <input
              type="text"
              class="form-control"
              placeholder="价格"
              v-model.number="price"
            />
          </div>
        </div>
        &nbsp;&nbsp;&nbsp;&nbsp;
        <!-- 阻止表单提交 -->
        <button class="btn btn-primary" @click.prevent="addBtn">
          添加资产
        </button>
      </form>
    </div>
  </div>
</template>

<script>
import moment from "moment";
export default {
  data() {
    return {
      name: "", // 名称
      price: 0, // 价格
      list: JSON.parse(localStorage.getItem("plist")) || [],
      /*  [
        { id: 100, name: "外套", price: 199, time: new Date("2010-08-12") },
        { id: 101, name: "裤子", price: 34, time: new Date("2013-09-01") },
        { id: 102, name: "鞋", price: 25.4, time: new Date("2018-11-22") },
        { id: 103, name: "头发", price: 19900, time: new Date("2020-12-12") },
      ], */
    };
  },
  methods: {
    delBtn(id) {
      this.list = this.list.filter((item) => item.id !== id);
    },
    addBtn() {
      if (this.name.trim() === "" || this.price === 0)
        return alert("信息不完整，重新输入");
      this.list.push({
        id: +new Date(),
        name: this.name,
        price: this.price,
        time: new Date(),
      });
    },
  },
  filters: {
    getTime(val) {
      return moment(val).format("YYYY-HH-DD");
    },
  },
  computed: {
    all() {
      return this.list.reduce((prev, item) => (prev += item.price), 0);
    },
    avg() {
      return (this.all / this.list.length).toFixed(2);
    },
  },
  watch: {
    list: {
      deep: true,
      immediate: true,
      handler(newVal, oldVal) {
        localStorage.setItem("plist", JSON.stringify(this.list));
      },
    },
  },
};
</script>

<style >
.red {
  color: red;
}
</style>